Between grassroots and elites? Assessing congruence between staffers and party members

This paper examines whether political professionalization causes ideological incongruence between party strata. For the first time ever, this unique study analyzes the internal opinion structure of 5 Flemish political parties by comparing the ideological preferences of staffers and party members. Breaking new theoretical ground, the paper builds on May's law of curvilinear disparity, literature on political professionalization and cleavage theory to predict and interpret (in)congruences between staffers and party members. The analysis is based on the combination of original survey data collected among the staff of 5 Flemish Belgian parties (N=560) with survey data collected among their party members by the MAPP project (N=10.022). Congruence between both groups is measured in-depth, covering 7 salient political issues including socioeconomic issues, socio-cultural policies and globalization. The results demonstrate that staffers are mostly congruent with party members, with a few remarkable exceptions. As anticipated by my reinterpretation of cleavage theory, incongruences are more prevalent among mainstream parties and mostly appear on issues concerning globalization. This cosmopolitan bias among staffers is primarily driven by an educational-and generational divide with party members. In the future, these educational and generational contrasts within parties could fuel genuine disagreements between party strata, especially in mainstream parties with old, shrinking membership bases